The prior art contains various structures which are designed to use grooves, channels, slots, or other openings therein, to hold an element for which the opening was provided. One such structure, for example, is the peripheral slot contiguous to the top at the inside of a swimming pool wall in which the peripheral bead, at the top of the flexible plastic swimming pool liner, is inserted to suspend the liner in position. While provision may be made in the design of such structures for securing additional desired accessories or elements, such "special" provision would add substantially to the cost and, in a standard design, when the additional accessory is not desired or not used, such additional grooves, channels, or other openings, present an unsightly appearance. Moreover, in many pre-existing arrangements, it would be desirable if an accessory receptor device could be conveniently and economically retrofitted onto an existing structure.
Also, in the past, when additional accessories are found to be desirable, a separate holding means for the additional accessory has been provided. This is the situation, for example, with reference to the arrangement presented in U.S. Pat. No. 4,457,119 where an additional (a second) channel or groove is provided in the coping member; the lower cannel being used to hold the peripheral bead of the swimming pool liner and the upper channel being used to hold another member, such as a cover.
Accordingly, a need exists for a novel receptor device, which is unique in structure and performance and also has the advantage of being retrofittable, that permits an accessory to be attached therein and be secured within the receptor device.